scholarly journals Effect of preheating on cytotoxicity and physicochemical properties of light-cured calcium-based cements.

2020 ◽  
Vol 33 (2) ◽  
pp. 82-89
Author(s):  
Diana Borghetti ◽  
Roberto Zimmer ◽  
Fernando Portella ◽  
Eduardo Reston ◽  
Celso Klein-Junior ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Physicochemical Properties ◽  
Cell Viability ◽  
Statistical Tests ◽  
Degree Of Conversion ◽  
Mtt Test ◽  
Low Degree ◽  
Loss Of Mass ◽  
Soluble Material ◽  
Positive Effect

The aim of this study was to evaluate the degree of conversion, cytotoxicity, solubility and pH of photopolymerizable calciumbased cements submitted to preheating. The degree of conversion was analyzed by Fourier transform infrared, cytotoxicity by the MTT test and solubility through loss of mass. The data were subjected to statistical tests (ANOVA / Tukey's, p<0.05). The photopolymerizable materials showed a low degree of conversion, regardless of preheating. All materials caused a reduction in cell viability at 24 hours and 7 days, with the Dycal (control) being more cytotoxic. Heat had a positive effect on Biocal at 7 days. Dycal is the most soluble material. Heat had no effect on the solubility or pH of the polymerizable materials. It is concluded that photopolymerizable calcium-based cements have a low degree of conversion and are soluble, which results in mild to moderate cytotoxicity.

scholarly journals Cytotoxicity and degree of conversion of methacrylate and silorane

2020 ◽  
Vol 19 ◽  
pp. e200656
Author(s):  
Virgínia Angélica Silva ◽  
Sávio Morato de Lacerda Gontijo ◽  
Alexandre Gatti ◽  
Luiz Thadeu de Abreu Poletto ◽  
Hugo Henriques Alvim
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Cell Viability ◽  
Fourier Transform Infrared Spectroscopy ◽  
Mtt Assay ◽  
Composite Resin ◽  
Fourier Transform Infrared ◽  
Degree Of Conversion ◽  
Similar Degree ◽  
Bonferroni Correction

Composites have been proven to have a cytotoxiceffect on a variety of tissues and cells. Aim: The aim of thisstudy was to analyse the degree of conversion of resinsand its correlation with the cell viability in primary gingivalfibroblasts. Methods: Resin-based silorane (Filtek P90)and conventional methacrylate resins (Filtek Z100, FiltekZ250 and Filtek Z350XT) were used to evaluate cell viabilityand the degree of conversion. The resins were light-cured bya LED for 20 and 40 seconds. The degree of conversion wasanalysed by Fourier transform infrared spectroscopy. Cellularmetabolism was evaluated after 24 hours by the MTT assay(n = 6) using the storage solution of composite resin foreither 24 hours or 12 days. Variance analysis (ANOVA) witha Bonferroni correction (p < 0.05) was performed to comparethe groups. Results: The composite Filtek P90 showed ahigher degree of conversion when polymerised for 40 or20 seconds, while the composites Filtek Z100, Filtek Z250 andFiltek Z350XT showed similar degree of conversion. Only theFiltek Z100 resin was cytotoxic. Conclusion: We found nostatistically significant correlation between cell viability andthe degree of conversion.

scholarly journals In Vitro and In Vivo Efficacy of New Composite for Direct Pulp Capping

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Julianne Coelho Silva ◽  
Tainah Oliveira Rifane ◽  
Antônio Ernando Ferreira-Junior ◽  
Ana Paula Alves ◽  
Richard Miron ◽  
...  
Keyword(s):  
Flexural Strength ◽  
Physicochemical Properties ◽  
Cell Viability ◽  
Statistical Difference ◽  
Calcium Release ◽  
Degree Of Conversion ◽  
Direct Pulp Capping ◽  
Pulp Capping

Objectives. To investigate physicochemical properties, dentin bonding, cytotoxicity, and in vivo pulp response of experimental self-adhesive composites tailored to direct pulp capping. Materials and Methods. Experimental composites were prepared with beta-tricalcium phosphate and hydroxyapatite nanoparticles adsorbed with simvastatin and glutathione added at 0% (control resin), 1 wt% (Res 1%), and 10 wt% (Res 10%). A commercial light-curable calcium hydroxide (Ca(OH)2) (Ultra-Blend Plus) was used as control material. The physicochemical properties investigated were flexural strength and modulus, calcium release, and degree of conversion. Dentin bonding was assessed by the push-out test. Proliferation and cell counting assays were performed to evaluate in vitro cytotoxicity using fluorescence microscopy. In vivo pulp capping was performed on molars of Wistar rats, which were euthanized after 14 days and evaluated by histological analysis. Results. No statistical difference was observed in flexural strength and cell viability ( p > 0.05 ). Res 10% presented higher modulus than control resin and Ca(OH)2. Also, Res 10% attained statistically higher degree of conversion when compared to other experimental composites. Ca(OH)2 showed higher calcium release after 28 and 45 days of storage, with no statistical difference at 45 days to Res 10%. All experimental composites achieved significantly higher bond strength when compared to Ca(OH)2. While no significant difference was observed in the cell proliferation rates, resins at lower concentrations showed higher cell viability. In vivo evaluation of pulp response demonstrated no pulp damage with experimental composites. Conclusions. The experimental composite investigated in this study achieved adequate physicochemical properties with minor in vivo pulpal inflammation and proved to be a valuable alternative for direct pulp capping.

Effect of Compensation and Work Environment on Employee Performance with Employee Job Satisfaction as an Intervening Variable

2018 ◽  
Vol 9 (03) ◽  
pp. 20553-20562
Author(s):  
Putu Ayu Diah Juliarti ◽  
Anak Agung Putu Agung ◽  
I Nengah Sudja
Keyword(s):  
Job Satisfaction ◽  
Work Environment ◽  
High Performance ◽  
Employee Performance ◽  
Statistical Tests ◽  
Path Coefficient ◽  
Significant Positive Effect ◽  
Organizational Goals ◽  
Record Keeping ◽  
Positive Effect

An employee who has a high performance and better able to support the achievement of the goals and objectives set by the company. Employees can work well if you have a high performance that can produce good work anyway. With the high- performance that employees, is expected to achieve organizational goals. This study examines the effect of compensation and work environment on employee performance with job satisfaction to be intervening variable. Data on compensation, work environment, job satisfaction, and employee performance obtained through observation, record keeping and questioner with respondents. The data obtained are then analyzed using Partial Least Squares (PLS). Statistical tests results showed  (1) the compensation proved significant positive effect on job satisfaction the path coefficient of 0.434 and T-Stats for 4.880, (2) work environment proved to be a significant positive effect on job satisfaction the path coefficient of 0.434 and T-Stats for 4.074, (3) job satisfaction proved to be a significant positive effect on employee performance the path coefficient of 0.264 and T-Stats for 2.458, (4) compensation proved positive and significant effect employee performance the path coefficient of 0.242 and T-Stats for 2.912, (5) work environment proved positive and significant effect employee performance the path coefficient of 0.378 and T-Stats for 3.343. Based on test results obtained statistical results of all variables positive and signicant impact.

Pengaruh Sistem Pengendalian Internal Pemerintah dan Kompetensi Pegawai Terhadap Kinerja Instansi Pemerintah Kabupaten Karimun

2020 ◽  
Vol 5 (1) ◽  
pp. 101-106
Author(s):  
Doni Putra Utama
Keyword(s):  
Control System ◽  
Control Systems ◽  
Internal Control ◽  
Statistical Tests ◽  
Government Agencies ◽  
Government Performance ◽  
Significant Positive Effect ◽  
Internal Control System ◽  
Employee Competencies ◽  
Positive Effect

This research is a causality study with the title "Effect of Government Internal Control Systems and Employee Competence on the Performance of Government Agencies in Karimun Regency." The purpose of this study was to determine the effect of the implementation of the Government's Internal Control System on the performance of Karimun Regency government agencies and to determine the effect of employee competence on the performance of Karimun Regency government agencies. Data collection using a questionnaire where the questionnaire contained questions about the Government's Internal Control System, employee competencies and agency performance. Data were tested using multiple linear regression statistical tests. Based on the results of the study, it can be concluded that the governmental internal control system has a significant positive effect on Government Agency Performance with the results of statistical tests that show a sig value of 0.016 <0.05 (alpha 5%). Employee Competency has a significant positive effect on Government Performance with the results of statistical tests showing a sig value of 0,000.

Effect of various cations on the initial rate of formation of peroxodisulphates

1980 ◽  
Vol 45 (8) ◽  
pp. 2272-2282 ◽  
Author(s):  
Jan Balej ◽  
Martin Kadeřávek
Keyword(s):  
Sulphuric Acid ◽  
Oxygen Evolution ◽  
Anodic Polarization ◽  
Initial Rate ◽  
Degree Of Conversion ◽  
Polarization Curves ◽  
Mixed Solutions ◽  
Low Degree ◽  
Partial Polarization

Preparation of peroxodisulphates by electrolysis of mixed solutions of sulphuric acid and various sulphates was studied at low degree of conversion; the partial polarization curves of peroxodisulphate formation and of oxygen evolution obtained from the overall anodic polarization curves and current yields of the principal anodic processes were examined. The mechanism of the effect of various cations on the rate of anodic formation of peroxodisulfates is discussed.

Effect of Irradiance and Exposure Duration on Temperature and Degree of Conversion of Dual-Cure Resin Cement for Ceramic Restorations

2018 ◽  
Vol 43 (6) ◽  
pp. E280-E287 ◽  
Author(s):  
JS Shim ◽  
SH Han ◽  
N Jha ◽  
ST Hwang ◽  
W Ahn ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Exposure Duration ◽  
Near Infrared ◽  
Degree Of Conversion ◽  
Resin Cement ◽  
Resin Cements ◽  
Digital Thermometer ◽  
Light Curing ◽  
Ceramic Restorations

SUMMARY This study investigated the effects of irradiance and exposure duration on dual-cured resin cements irradiated through ceramic restorative materials. A single light-curing unit was calibrated to three different irradiances (500, 1000, and 1500 mW/cm2) and irradiated to three different attenuating materials (transparent acryl, lithium disilicate, zirconia) with 1-mm thicknesses for 20 or 60 seconds. The changes in irradiance and temperature were measured with a radiometer (or digital thermometer) under the attenuating materials. The degree of conversion (DC) of dual-cure resin cement after irradiation at different irradiances and exposure durations was measured with Fourier transform near infrared spectroscopy. Two-way analysis of variance revealed that irradiance (p&lt;0.001) and exposure duration (p&lt;0.001) significantly affected temperature and DC. All groups showed higher DCs with increased exposure times (p&lt;0.05), but there were no statistically significant differences between the groups irradiated with 1000 mW/cm2 and 1500 mW/cm2 (p&gt;0.05). Higher-intensity irradiances yielded higher temperatures (p&lt;0.05), but exposure time did not affect temperature when materials were irradiated at 500 mW/cm2 (p&gt;0.05).

Fabrication and Characterization of Graphene Nanofibers by Electrospinning Technique and Its Electrochemical Properties

2020 ◽  
Vol 20 (12) ◽  
pp. 7659-7664
Author(s):  
Senthilkumar Jayanthi ◽  
Thirugnanam Lavanya ◽  
Mrinal Dutta ◽  
Nagarajan Anbil Saradha ◽  
Kaveri Satheesh
Keyword(s):  
Fourier Transform ◽  
Physicochemical Properties ◽  
Fabrication Method ◽  
Electrospinning Technique ◽  
Raman Spectroscopic ◽  
Reduced Graphene ◽  
Electrospinning Method ◽  
Fabrication And Characterization ◽  
20 Nm

Graphene has proved to be superior material for its exceptional physicochemical properties. However engineering graphene macroscopic structures by manipulating microscopic structures has faced a great challenge. Towards this here we report a fabrication method of graphene nanofiber by using simple electrospinning method. Fourier transform infrared and Raman spectroscopic characterizations confirmed the transformation from GO to reduced graphene for the nanofiber material. Estimated surface area of this material is as high as 526 m2g−1 with pores having size around 20 nm. Specific-capacitance of these nanofibers for current-density of 1 Ag−1 is 144.2 Fg−1, which will be useful for the advancement of devices for storing energy.

scholarly journals THE EFFECT OF POULTRY MANURE AND LIME AMELIORANT ON ACID-BASIC PROPERTIES OF LEACHED BLACK SOIL (CHERNOZEM) AND THE YIELD OF CROPS

2020 ◽  
pp. 65-72
Author(s):  
Н.П. Чекаев ◽  
Е.Г. Куликова ◽  
А.В. Леснов
Keyword(s):  
Physicochemical Properties ◽  
Dry Matter ◽  
Field Experiments ◽  
Poultry Manure ◽  
Black Soil ◽  
Chicken Manure ◽  
Leached Chernozem ◽  
Positive Effect ◽  
Different Doses ◽  
Experimental Plots

В статье показаны результаты трехлетних полевых опытов по изучению влияния разных доз куриного помета и известкового мелиоранта на физико-химические свойства чернозема выщелоченного и урожайность возделываемых сельскохозяйственных культур на опытных участках. В результате проведенных исследований на опытном поле ФГБОУ ВО Пензенский ГАУ (Пензенская область, Мокшанский район) было выявлено, что при внесении разных доз куриного помета в последействии на второй и третий год наблюдается увеличение кислотности. Использование известкового мелиоранта снижает подкисление и повышает эффективность внесенных доз куриного помета. Применение доз куриного помета от 2 до 10 т/га из расчета на сухое вещество положительно влияли на урожайность зерна как первой культуры после внесения, так второй и третьей. Наибольшую продуктивность исследуемых культур наблюдали на вариантах с внесением от 6 до 10 т/га помета. На фоне известкования эффективность их применения увеличивалась. The article shows the results of three-year field experiments to study the effect of different doses of chicken manure and lime ameliorant on the physicochemical properties of leached chernozem and the yield of cultivated crops in the experimental plots. The studies were carried out on the experimental field of Penza State Agrarian University (Penza Region, Mokshansky District). As a result of, it was revealed that when different doses of chicken manure were applied, an aftereffect increase in acidity was observed in the second and third years. The use of a lime ameliorant reduces acidification and increases the effectiveness of the applied doses of chicken manure. The use of doses of chicken manure from 2 to 10 t/ha (dry matter) had a positive effect on the grain yield of both the first crop after application, and the second and third. The highest productivity of the studied crops was observed in the variants with the introduction of 6 to 10 t/ha of manure. Against the background of liming, the effectiveness of their application increased.

PENGARUH LABEL HALAL TERHADAP KEPUTUSAN MASYARAKAT MEMBELI PRODUK MAKANAN DAN MINUMAN (Studi Kasus Lingkungan VI Kelurahan Nangka Binjai Utara)

2020 ◽  
Vol 5 (2) ◽  
pp. 354
Author(s):  
Raja Sakti Putra Harahap
Keyword(s):  
Regression Model ◽  
Quantitative Method ◽  
Statistical Tests ◽  
A Value ◽  
Regression Formula ◽  
Simple Regression Model ◽  
Food And Beverage ◽  
R Value ◽  
Positive Effect ◽  
Simple Regression

This study aims to determine how the effect of the halal label on people’s decisions to buy food and beverage products. The method used is a quantitative method with a simple regression model and using statistical tests with the help of IBM SPSS Statistics 22 for windows. The sample in this study is the neighborhood community VI Nangka Village as many as 70 respondents. The results showed that the calculated r value was 0,79, so it could be saidthat there was s relationship or correlation between the variables X (Halal Label) with the variable Y ( The decision to buy food and beverage products). Then the t value &lt; t table, which has a value of 0,657 &lt; 1,668. Then  is accepted and  is rejected, which means that partially (X) variable does not have a significant effect on variable (Y), where the results of the hypothesis are accepted and proven after being calculated using a simple regression formula, namely Y = 34,7 + 0,67X.  By having a regression coefficoent of 0,675%, so the halal label has a positive effect on decisions to buy food and beverage products.

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